“…In order to establish physics laws for particle volume‐potentials, we analyze experimental data for the behavior of partial particle volumes (v 1 or v 2 ) through the following method. Since the volume V of a granular system is an extensive variable, which is homogeneous of degree 1, based on Euler's theorem for homogeneous function (Silbey et al., 2005, Chang & Deng,
2022), the total volume of a mixture can be expressed as
…”